Optical-interference type reflective panel and method for making the same

ABSTRACT

An optical-interference type reflective panel and a method for making the same are disclosed, wherein the display panel has a substrate on which multiple supporting layers are firstly formed. Then, a plurality of first conductive optical film stacks, spacing layers and multiple second conductive optical film stacks are sequentially formed on the substrate. Finally, once the spacing layers are removed, optical-interference regulators are formed. Since said supporting layers forming step is prior to the first conductive optical film stacks, a precise back-side exposing step is not necessary so that the making procedure of the panel is simplified.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to an optical-interference typereflective panel and a method for making the same, and more particularlyto a reflective panel for which a supporting layer forming step is priorto a first conductive optical film stack forming step so as to simplifythe manufacturing process of the reflective panel.

[0003] 2. Description of Related Art

[0004] In order to minimize the bulky size of a computer display, theflat display was developed to replace the conventional CRT display. Forexample, the most well known flat display is the LCD. In recent years,different kinds of LCDs have been developed by display manufacturers.Most of these manufacturers are dedicated as far as possible to reducethe power consumption of the display so that the LCD will become moresuitable for portable electronic products such as cell phones, PDAs andE-books.

[0005] Inside the LCD device, the back light module consumes the mostpower of all the elements. To solve the problem, a reflective type panelis developed, which utilizes the external light as the light source toreplace the back light module.

[0006] Whether for the conventional LCD panel or the reflective typepanel, a color filtering film and a polarizing film are constructed inthe panel so as to display the color images and control the direction ofthe light. Even though these thin films are pervious to light, a partialamount of light may be blocked or lost while light passes through thesefilms. To overcome the light loss problem, another reflective type panelcalled an optical-interference panel has accordingly been developed.Based on the interference phenomenon caused when light passes throughdifferent thin films, the aforementioned optical-interference panel isable to generate the fundamental red, blue and green colors by properlycreating the thin film elements. Thus, the panel is able to show colorimages without the use of said color filter thin film and polarizingthin film, meanwhile the light transmittance of the panel is alsoimproved so the panel is much more suitable to be applied to theportable electronic products.

[0007] With reference to FIG. 3, a single optical-interference regulatorin the aforementioned optical-interference panel includes a substrate(70), a first conductive optical film stack (71) and a supporting layer(72) formed on the substrate (70). A second conductive optical filmstack (73) (also called amechanical layer) partly covers the adjacentsupporting layers (72), whereby a gap is defined between the first andsecond conductive optical film stacks (71, 73).

[0008] When supplying an electrical field between the two conductiveoptical film stacks (71, 73) by an external driving circuit (not shown),the second conductive optical film stack (73) will be slightly deformedand becomes closer to the first conductive optical film stack (71). Withthe different gap distances between the two conductive optical filmstacks (71,73), light beams passing through the panel will havedifferent extents of interference, so that the panel is able to showdifferent colors.

[0009] However, the fabricating process of the conventional panel isquite complex. With reference to FIGS. 4A and 4B, the first conductiveoptical film stack (71) and a spacing layer (701) are sequentiallyformed on the substrate (70) by well known film deposition,photolithography, film etching steps etc.

[0010] A negative photo-resist layer (not shown) is then applied on thesurfaces of the first conductive optical film stack (71) and the spacinglayer (701). With the steps of back-side exposing and photolithography,parts of the first conductive optical film stack (71) are removed fromthe substrate (70). The exposed regions of the substrate (70) areprovided to form multiple supporting layers (72) thereon as shown inFIG. 4C.

[0011] With reference to FIG. 4D, the second conductive optical filmstack (73) is formed on all supporting layers (72) and the spacing layer(701). In FIG. 4D, after removing the spacing layer (701) from thesubstrate (70), a gap is accordingly defined between the first and thesecond conductive optical film stacks (71)(73).

[0012] In the foregoing processes, since the first conductive opticalfilm stack (71) is formed on the substrate (70) prior to the supportinglayers (72), a precise self-alignment process (back-side exposing) isinvolved when applying the negative photo-resist layer on the firstconductive optical film stack (71) and the spacing layer (701). Thus,the entire panel manufacturing process is particularly complex.

[0013] To mitigate and/or obviate the aforementioned problem, thepresent invention provides a novel optical-interference type reflectivepanel and a method for making the same.

SUMMARY OF THE INVENTION

[0014] One objective of the present invention is to provide anoptical-interference type reflective panel and a method for making thesame, wherein the manufacturing procedure for the panel is simplified.

[0015] To accomplish the objective, the method has the steps of:

[0016] providing a substrate;

[0017] sequentially forming a plurality of supporting layers, firstconductive optical film stacks, a spacing layer and a plurality ofsecond conductive optical film stacks on the substrate; and

[0018] removing the spacing layer from the substrate to formoptical-interference regulators on the substrate.

[0019] Because said supporting layers forming step is prior to the firstconductive optical film stacks, a precise back-side exposing step is notnecessary so that the fabricating procedure of the panel is simplified.

[0020] Other objects, advantages and novel features of the inventionwill become more apparent from the following detailed description whentaken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] FIGS. 1A-1E show a manufacturing process of an opticalinterference panel in accordance with the present invention;

[0022] FIGS. 2A-2D show different embodiments of the first conductiveoptical film stacks;

[0023]FIG. 3 is a cross sectional view of a single pixel of a conventionoptical-interference panel; and

[0024] FIGS. 4A-4E show a conventional manufacturing process of thepixel of FIG. 3.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

[0025] With reference to FIGS. 1A to 1E, a manufacturing process of anoptical interference panel in accordance with the present invention isdisclosed. The process includes the following steps.

[0026] As shown in FIG. 1A, a plurality of the supporting layers (11) isformed on a substrate (10) that is composed of glass or macromoleculematerial.

[0027] In FIG. 1B, a first conductive optical film stack (12) is thenformed on the substrate (10) and between adjacent supporting layers(11), wherein the first conductive optical film stack (12) also covers apartial surface of the adjacent supporting layers (11).

[0028] With reference to FIG. 1C, a spacing layer (13), which is alsocalled a sacrificing layer, is applied on the entire substrate (10) andflattened.

[0029] With reference to FIG. 1D, a second conductive optical film (14)is formed on the spacing layer (13) and between the adjacent supportinglayers (11).

[0030] In FIG. 1E, the spacing layer (12) is removed from the substrate(10), whereby the second conductive optical film (14) is sustained bythe adjacent supporting layers (11) via the first conductive opticalfilm stack (12), and a gap is defined between the first and the secondconductive optical film stacks (12)(13). The structure shown in FIG. 1Eis also called an optical interference regulator.

[0031] In the foregoing process, the supporting layer (11) forming isaccomplished by usual exposing and photolithography steps withoutinvolving a back-side exposing technology.

[0032] With reference to FIGS. 2A-2D, said first conductive optical filmstack (12) may be formed by different embodiments. In FIG. 2A, the firstconductive optical film stack (12) is sequentially composed of atransparent conductive layer (121), an absorption layer (122 a) and adielectric layer (124 a) according to a sequence from the bottom to thetop.

[0033] As shown in FIG. 2B, the first conductive optical film stack (12)is sequentially composed of a transparent conductive layer (121 b), afirst dielectric layer (123 b), an absorption layer (122 b) and a seconddielectric layer (124 b).

[0034] As shown in FIG. 2C, the first conductive optical film stack (12)is sequentially composed of a first dielectric layer (123 c), atransparent conductive layer (121), an absorption layer (122 bc and asecond dielectric layer (124 c).

[0035] As shown in FIG. 2D, the first conductive optical film stack (12)is sequentially composed of a first dielectric layer (123 d), anabsorption layer (122 d), a transparent conductive layer (121 d) and asecond dielectric layer (124 d). Further, at least one opticalreflective layer is composed in the second conductive optical film stack(14).

[0036] Since the manufacturing process of the present invention does notneed a precise alignment step, the supporting layers (11) are partlyoverlapped by the first conductive optical film stack (12). Thus, saidsecond conductive optical film stack (14) is accordingly formed abovethe first conductive optical film stack (12).

[0037] With the foregoing description, the panel manufacturing procedureis simplified because the precise alignment step is not required anymore. Accordingly, the producing efficiency is able to be improved.

[0038] It is to be understood, however, that even though numerouscharacteristics and advantages of the present invention have been setforth in the foregoing description, together with details of thestructure and function of the invention, the disclosure is illustrativeonly, and changes may be made in detail, especially in matters of shape,size, and arrangement of parts within the principles of the invention tothe full extent indicated by the broad general meaning of the terms inwhich the appended claims are expressed.

What is claimed is:
 1. A method for making an optical interference typereflective panel, the method comprising the steps of: providing asubstrate (10); sequentially forming a plurality of supporting layers(11), a plurality offirst conductive optical film stacks (12), a spacinglayer (13) and a plurality of second conductive optical film stacks (13)on the substrate (10); and removing the spacing layer (13) from thesubstrate (10) to form optical-interference regulators on the substrate.2. The method as claimed in claim 1, the method further comprising thesteps of: forming the plurality of supporting layers (11) on thesubstrate (10); forming the first conductive optical film stacks (12) onthe substrate (10) and between adjacent supporting layers (11); formingthe spacing layer (13) on the substrate (10), wherein the spacing layer(13) is flattened; forming the second conductive optical film stacks(14) above the adjacent supporting layers (11); and removing the spacinglayer (13), wherein once the spacing layer (13) has been removed fromthe substrate (10), a gap is defined between the first and the secondconductive optical film stacks (12)(14) and the second conductiveoptical film stack is sustained by the adjacent supporting layers (11).3. The method as claimed in claim 1, wherein the first conductiveoptical film stack (12) covers a part of the adjacent supporting layers(11), and the second conductive optical film stack (14) is formed aboveregions where the first conductive optical film stack (12) overlaps theadjacent supporting layers (11).
 4. The method as claimed in claim 2,wherein the first conductive optical film stack (12) covers a part ofthe adjacent supporting layers (11), and the second conductive opticalfilm stack (14) is formed above regions where the first conductiveoptical film stack (12) overlaps the adjacent supporting layers (11). 5.The method as claimed in claim 1, wherein the substrate (10) is composedof glass or macromolecule material.
 6. The method as claimed in claim 2,wherein the substrate (10) is composed of glass or macromoleculematerial.
 7. The method as claimed in claim 1, wherein the firstconductive optical film stack (12) is composed of a transparentconductive layer (121), an absorption layer (122) and at least onedielectric layer (124).
 8. The method as claimed in claim 2, wherein thefirst conductive optical film stack (12) is composed of a transparentconductive layer (121), an absorption layer (122) and at least onedielectric layer (124).
 9. The method as claimed in claim 1, wherein thesecond conductive optical film stack (14) contains at least one opticalreflective layer therein.
 10. The method as claimed in claim 2, whereinthe second conductive optical film stack (14) contains at least oneoptical reflective layer therein.
 11. An optical interference reflectivepanel comprising: a substrate (10); a plurality of supporting layers(11) formed on the substrate (10); a plurality of first conductiveoptical film stacks (12) formed on the substrate (10), wherein eachfirst conductive optical film stack (12) is formed between adjacentsupporting layers (11) and covers a part of the adjacent supportinglayers (11); and a plurality of second conductive optical film stacks(14) formed above the first conductive optical film stacks (12), whereinthe second conductive optical film stacks (14) partly overlap regionswhere the first conductive optical film stacks (12) are formed above theadjacent supporting layers (11).
 12. The reflective panel as claimed inclaim 11, wherein the substrate (10) is composed of glass ormacromolecule material.
 13. The reflective panel as claimed in claim 11,wherein the first conductive optical film stack (12) is composed of atransparent conductive layer (121), an absorption layer (122) and atleast one dielectric layer (124).
 14. The reflective panel as claimed inclaim 11, wherein the second conductive optical film stack (14) containsat least one optical reflective layer therein.